1. Field of the Invention
The invention, according to a first aspect, pertains to a hub for a clutch disk arrangement with at least two friction lining units, where at least one of the friction lining units can be shifted relative to one of the other friction lining units in a direction parallel to an axis of rotation, especially for a friction clutch designed as a multi-disk clutch. The invention, according to a second aspect, also pertains to a clutch disk arrangement for a friction clutch designed as a multi-disk clutch.
2. Description of the Related Art
A known hub includes a hub element which can be connected nonrotatably to a shaft, and a circumferential engagement formation serving to drive at least one friction lining unit in rotation, which formation is located on a connecting side of a torque-transmitting arrangement connected to the hub element and can be brought into engagement for rotation in common with an opposing engagement formation of the friction lining unit or of the assigned friction lining unit.
A hub of the type indicated is known, for example, from U.S. Pat. No. 6,464,058. The known hub has a ring element, executed as a sheet-metal part, which has a profile designed to accept the torque to be introduced from friction linings to a shaft. The hub also has a driver with a hub element for transmitting the torque. The driver is also made as a sheet-metal part, and the shape of its radially outer area corresponds to that of the ring element.
A known clutch disk arrangement includes at least two friction lining units; a hub element, which is or can be connected nonrotatably to a shaft; a carrier arrangement, to which the friction lining units are connected at least essentially nonrotatably and by means of which the friction lining units are or can be connected to the hub element; and a torsional vibration damper arrangement, which has a central disk element either permanently connected to the hub element or formed as a one-piece unit with it; two cover disk elements, one on each axial side of the central disk element, which are free to rotate to at least a limited extent relative to the hub element; and a damping and/or spring element arrangement, which acts between the central disk element and the cover disk element. The carrier arrangement includes a first carrier element, which is or can be connected via the torsional vibration damper arrangement to the hub element, and which is either permanently connected to one of the cover disk elements or made as a one-piece unit with it, to which first carrier element one of the friction lining units is permanently connected; and a second carrier element, which is or can be connected via the torsional vibration damper arrangement to the hub element, to which second conductor element another one of the friction lining units is permanently connected and which is or can be connected to the first carrier element for rotation in common while at the same time being free to shift position relative to the first element essentially in the direction parallel to an axis of rotation.
A clutch disk arrangement of the type in question is known, for example, from U.S. Pat. No. 6,793,058; reference is made to FIG. 8 in that document. A clutch disk arrangement of this type is suitable, for example, for use in combination with a pressure plate assembly such as that known from U.S. Pat. No. 6,409,002 to obtain a corresponding multi-disk clutch. In the known clutch disk arrangement, the second carrier element is arranged on the first carrier element so that it can shift position in a direction parallel to the axis of rotation, where an outer set of teeth on the first carrier element engages for rotation in common with an inner set of teeth on the second carrier element. The two carrier elements are each designed in the form of cups, where the outer teeth of the first and the inner teeth of the second carrier element are formed on sections of the circumferential walls of the two elements. These circumferential wall areas, which extend in the axial direction, bridge an axial gap, the size of which depends on the minimum axial distance between the friction lining units. The known dual clutch disk therefore takes up a comparatively large amount of radial and axial space radially inside the friction lining units; allowances for this space requirement must be made either on the engine side or on the transmission side, and it is also necessary on the gearbox side to allow room for the actuation of the clutch during the clutch-releasing-and-engaging process and possibly for the inward travel of the spring tongues of a diaphragm spring, which serves as a force storage device.
With respect to the coupling of the two carrier elements by means of their teeth, it is observed that the production of these types of toothed rims is comparatively complicated technically and is therefore also comparatively expensive.